Electrode for discharge tubes



Sept- 1934- R. A. WARREN 1,972,611

ELECTRODE FOR DISCHARGE TUBES Filed Dec. 15, 1932 Patented Sept. 4, 1934 UNITED STATES PATENT orricg 3 Claims.

This invention relates to improvements in electrodes of discharge tubes such as neon and other rare gas or gas mixture tubes and consists of the matters hereinafter described and more particularly pointed out in the appended claims.

The familiar elongated tubular metal electrodes of the Claude type are mounted in the glass discharge tube at its ends in close proximity to the glass wall of the tube. The electrade is supported at its closed end by the'lead wires which are sealed in the proximate closed end of the discharge tube. Thus the one end of the electrode is supported concentrically within the glass tube and is held in proper spaced relation to the wall of said tube. Various means 'have been employed to support the discharge end of said electrode and maintain itin similar concentric spaced relation within the tube. These means have consisted, for example, of glass beads strung about the forward end of the electrode between the electrode and the glass' wall of the tube and of a mica sleeve or sheath about the electrode. of the spacing means is insulation material.

I have discovered that a spacing member made of conducting material, such for example as nickel, iron, steel, or copper, the very metal of which the electrode itself is made, may be interposed about the electrode with the-same, if not superior, results and with greater economy, both in the cost of' material and in the cost of assembly.

The advantages of the invention will appear more clearly as I proceed with my specification.

In the drawing:

Figure 1 is a fragmentary view showing one end of a discharge tube with an electrode mounted and properly supported therein in accordance with my invention.

Figure 2 is a longitudinal section through the same.

Figure 3 is a longitudinal section similar to Figure 2, but showing a somewhat modified form ofthe invention.

wall of the tube. Means must also be provided either in the formation of the spacing member itself or otherwise to retain the spacing member in a location back of the discharge end of the electrode.

But in both cases, the material,

Figure 4 represents a typical cross section the space separating the electrode from the glass I Referring now to the drawing: 10 indicates the discharge tube; 11 indicates an electrode of the Claude'type, the same being an elongated tubular body closed at one end and located concentrically within and in narrow spaced relation tothe glass wall of the discharge tube within which it is mounted; and 12 indicates the lead-in wires, which are sealed in the closed end of the glass tube. 4

The lead-in wires 12, as heretofore pointed out, properly support the closed end of the electrode and hold it in suitable spaced relation within the discharge tube. Referring to Figures 1, 2 and 3, 13 indicates the novel spacing member. This consists of a comparatively narrow, thin, per-- stantially bridge, either directly or indirectly, the

space between the electrode and the glass wall of the tube, but to also frictionally maintain the position to which it is brought on the electrode.

'This position, as shown in the drawing, is back of and spaced from the discharge end of the electrode. The spacing back must be such that no dischargewillbe made from the forward end of the spacing means.

Instead .of the curled perforated band, an imperforate band, as for example, of copper or of other conductor, may'b'e employed as shown in Figure 3. In this case 130 indicates a spacing support. The perforations are used in the construction previously described in order to provide a springiness in the metal which aids in securing friction to maintain'the spacing device in place. Where an imperforate sheet of metal, such as that used to make the spacer shown in Figures 3 and 4 is used, friction may not be depended upon and I, therefore, provide a tongue or tongues 13b formed at the end of the spacer towards the closed end of the electrode to be bent down upon and engage said end of the electrode to maintain the spacer with its forward end back of the discharge end of the electrode.

*1 claim as my invention: 5 '1. In a discharge tube, in combination with a tubular electrode concentrically disposed therein, a spacing member consisting of a band of conductor material, wound about the electrode and frictionally engaged between said electrode and the glass wall of said discharge tube, said spacing member being spaced back of the discharge end of said electrode.

2. In a discharge tube, in combination with a tubular electrode concentrically disposed therein, a spacing member consisting of a band of conducting material wrapped about said electrode and interposed in supporting relation between said electrode and the glass wall of said discharge -tube, and means for maintaining said spacing 

